Which statement shows how two polynomials 3x + 6 and 5x2 - 4x demonstrate the closure property when multiplied?
O 15x3 + 18x? - 24x may or may not be a polynomial
O 15x3 + 18x2 - 24x is a polynomial
O 15x + 42x2 – 24x may or may not be a polynomial
15x3 + 42x2 - 24x is a polynomial